analytical and toxicological evaluation of flavor chemicals in electronic cigarette refill fluids

Introduction:
This text discusses a study that compares the cytotoxicity of electronic cigarette (e-cigarette) refill fluids and aerosols using different cell types. The study also evaluates the cytotoxicity of aerosols made from authentic propylene glycol and glycerin, the two most commonly used refill fluid solvents. The study aims to follow up on a previous publication dealing with the cytotoxicity of refill fluids.

Key Points:

* The study used 35 e-cigarette refill fluids and e-cigarette DIY products containing various flavourings and nicotine concentrations.
* The products were chosen to give a range of manufacturers, solvents, nicotine concentrations, and flavors.
* The refill fluids were stored at 4°C for 1 year before rescreening.
* E-cigarette aerosol was produced using a smoking machine and collected into culture medium in a round bottom flask submerged into an ice bath.
* Three different cell types were used: human pulmonary fibroblasts, a549 lung epithelial cells, and pluripotent human embryonic stem cells.
* The refill fluids and aerosols were tested in dose-response experiments using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to observe cytotoxic effects on the cells.
* The cytotoxicity of the refill fluids and aerosols was compared, and the cytotoxicity of aerosols made from authentic propylene glycol and glycerin was also evaluated.

Main Message:
The study found that various flavors/brands of e-cigarette refill fluids and their aerosols are cytotoxic, demonstrating the need for further evaluation of e-cigarette products to better understand their potential health effects. The study also highlights the importance of considering the cytotoxicity of refill fluids and aerosols when regulating e-cigarette products, as the cytotoxicity of some products varied significantly. additionally, the study found that stem cells were often more sensitive than differentiated cells to aerosols, suggesting that e-cigarette use may have harmful effects on human development. Overall, the study underscores the need for continued research and regulation of e-cigarette products to ensure their safety and public health.

Behar, Rachel Z., Wentai Luo, Kevin J. McWhirter, James F. Pankow, and Prue Talbot. “analytical and Toxicological Evaluation of Flavor Chemicals in Electronic Cigarette Refill Fluids.” Scientific Reports 8, no. 1 (May 29, 2018): 8288. https://doi.org/10.1038/s41598-018-25575-6.